A full-solid-waste high-erosion-resistant cementitious material composition and a preparation method thereof

Abstract

This application relates to the field of cementitious materials, specifically to a high corrosion-resistant cementitious material composition made entirely from solid waste and its preparation method. The composition comprises the following components in parts by weight: 0-40 parts of metal tailings, 40-85 parts of granulated blast furnace slag powder, 5-20 parts of gypsum, 0.5-3 parts of calcareous raw materials, and 0.01-6 parts of additives; the additives include at least one of activated calcium carbonate, activated alumina, and an accelerator. This application utilizes the above formulation to activate the hydration activity of metal tailings and granulated blast furnace slag powder through the compatibility of solid waste mineral phases and additives, without the need for high-temperature calcination. Activated calcium carbonate and activated alumina can induce the in-situ growth of two-dimensional hydration products of single-carbon hydrated calcium aluminate, effectively fixing harmful ions in the coastal environment and thus improving the corrosion resistance of this cementitious material. The addition of the accelerator can further optimize the hydration environment and improve the compactness and long-term durability of the cementitious material's microstructure.

Description

Technical Field

[0001] This application relates to the field of cementitious materials, specifically to a high corrosion-resistant cementitious material composition for solid waste and its preparation method. Background Technology

[0002] All-solid-waste cementitious materials use industrial and mining solid waste as raw materials, reducing the clinker coefficient in the cement industry, decreasing dependence on natural resources, lowering energy consumption and carbon emissions, and simultaneously achieving resource utilization of solid waste. However, due to the use of solid waste with lower hydration activity than clinker, the hydration process and the composition and evolution of hydration products in all-solid-waste cement differ significantly from ordinary silicate cement. This presents numerous challenges to material performance, especially in complex service environments such as coastal areas.

[0003] In marine environments, cement materials face erosion from various harmful ions, which significantly and adversely affect the microstructure of cement materials, especially cementitious materials with high solid waste content. Improving the erosion resistance of cementitious materials is crucial for ensuring the durability of concrete structures, and researchers both domestically and internationally have explored various methods to regulate and enhance this resistance. Regarding compositional design optimization, selecting appropriate cementitious material combinations, such as using sulfate-resistant cement or adding mineral admixtures (e.g., silica fume, slag powder), can improve the material's density and erosion resistance. However, the addition of these mineral admixtures may reduce early strength, and their resources are limited and costly. The use of chemical admixtures is also a common method; for example, adding corrosion inhibitors and rust inhibitors can effectively inhibit the corrosion of reinforcing steel and the erosion by harmful ions. However, there are many types of chemical admixtures, and improper selection may cause secondary pollution to the environment, and their long-term effects require further verification. In terms of gradation optimization, adjusting the particle size distribution of aggregates and the particle size distribution of cementitious materials can reduce the porosity of the material and improve its impermeability. However, optimizing the gradation requires precise control and is limited by aggregate supply and cost in practical engineering. In summary, although various methods can regulate and enhance the erosion resistance of cementitious materials, each method has certain shortcomings and limitations, and does not fundamentally solve the problem of insufficient erosion resistance of the hydration products themselves.

[0004] Therefore, developing a high-corrosion-resistant, low-carbon cementitious material for solid waste that has good early performance, low cost, and is environmentally friendly will not only help improve the utilization rate of solid waste resources and reduce the carbon footprint of the cementitious material industry, but also has important practical significance and application prospects for promoting the green and low-carbon development of marine engineering, coastal infrastructure, and solid waste building materials. Summary of the Invention

[0005] To address the problem of insufficient corrosion resistance in low-carbon cementitious materials with high solid waste content in coastal environments, this application provides a high corrosion-resistant cementitious material composition made entirely of solid waste. In a clinker-free low-carbon system, the composition achieves actively regulated high corrosion resistance of the low-carbon cementitious material with high solid waste content by inducing in-situ growth of two-dimensional hydration products.

[0006] In a first aspect, this application provides a high corrosion-resistant cementitious material composition for all solid waste, employing the following technical solution: A composition of a high corrosion-resistant cementitious material for solid waste, comprising the following components in parts by weight: Metal tailings 0-40 parts, granulated blast furnace slag powder 40-85 parts, gypsum 5-20 parts, calcareous raw materials 0.5-3 parts, additives 0.01-6 parts; The additive includes at least one of activated calcium carbonate, activated alumina, and accelerator; The activated calcium carbonate includes at least one of the following: carbonized steel slag, carbonized recycled micro powder, carbonized red mud, carbonized fly ash, silicon carbide calcium slag, and nano-calcium carbonate. The activated alumina includes at least one of fly ash, metakaolin, alumina slag, and nano-alumina; The accelerator includes at least one of triisopropanolamine, triethanolamine, sodium sulfate, sodium bicarbonate, polyaluminum chloride, sulfoaluminate cement clinker, sodium aluminate, and aluminum hydroxide.

[0007] By employing the above technical solution, metal tailings, slag powder, gypsum, and calcareous raw materials are compounded in a certain proportion. Without the need for high-temperature calcination, the hydration activity of the metal tailings and granulated blast furnace slag powder is activated through the compatibility of solid waste mineral phases and additives. Activated calcium carbonate and activated alumina can induce the in-situ growth of two-dimensional hydration products of single-carbon hydrated calcium aluminate, effectively fixing harmful ions in the coastal environment and thus improving the corrosion resistance of this cementitious material. The addition of accelerators can effectively promote the generation of hydration products, allowing more hydration products to fill the pores, increasing the density and structural stability of the cementitious material, thereby further improving its corrosion resistance and long-term durability. Furthermore, by supplementing with activated calcium carbonate, activated alumina, and chemical accelerators, the hydration products are generated more quickly in the early stages, effectively solving the problem of low early strength caused by the large-scale incorporation of low-activity tailings.

[0008] The formula achieves a high utilization rate of up to 40% for metal tailings, with an overall solid waste content of 100%, providing a large-scale disposal method for bulk metal tailings and industrial by-products such as gypsum and steel slag, which is of great environmental significance. The preparation process of the cementitious material does not involve high-temperature calcination, but only drying, grinding and mixing, which has significant safety, environmental protection and low-carbon advantages compared with traditional cement.

[0009] Preferably, the additive is an accelerator, and the accelerator is triisopropanolamine.

[0010] By employing the above technical solution, the molecular structure of triisopropanolamine contains an isopropyl side chain, while triethanolamine is a straight-chain ethyl group. The steric hindrance effect of the isopropyl group gives triisopropanolamine stronger stereoisomerism, significantly enhancing its adsorption capacity at the solid-liquid interface. Triisopropanolamine reduces the surface energy of slag particles, promotes uniform dispersion of mineral powder, increases the contact area for hydration reactions, and accelerates early CSH gel nucleation. At the same dosage, triisopropanolamine is more effective than triethanolamine in improving the fluidity of the gelation system, reducing water demand, and indirectly increasing density.

[0011] Triisopropanolamine's hydroxyl groups form chelate sites with its amino groups, preferentially adsorbing calcium ions released from slag to form soluble complexes. This promotes the migration of calcium ions to the reaction interface and accelerates the depolymerization of the slag glass. Triisopropanolamine specifically promotes the hydration of aluminoferrites, while triethanolamine mainly activates aluminates. In systems with a high slag content, the iron phase content is significantly higher than in traditional cement. Triisopropanolamine accelerates the reaction of iron / aluminum ions with gypsum to form hydrated calcium sulfoferrite (aluminate), shortening the setting time and improving 3-day strength. In the later stages, triisopropanolamine continues to promote the hydration of inert phases such as dicalcium silicate in the slag, generating more CSH gel and improving 28-day compressive strength.

[0012] Triisopropanolamine promotes the formation of large quantities of hydrated calcium sulfoferrate (aluminate) and CSH gel, filling capillary pores and reducing total porosity. The dense structure blocks chloride / sulfate ion penetration, increasing the corrosion resistance coefficient. The hydrated calcium sulfoferrate (aluminate) crystals induced by triisopropanolamine are finer and more uniformly distributed, reducing microcracks caused by local expansion stress and improving durability in coastal wet and dry cycles.

[0013] Preferably, the additive is an accelerator, which is a mixture of triisopropanolamine and sodium sulfate.

[0014] By employing the above technical solution, the isopropyl steric hindrance effect of triisopropanolamine enhances its chelating ability for iron / aluminum ions in slag, promoting the reaction of the iron-aluminate phase with gypsum to form hydrated calcium sulfoferrate (aluminate), while continuously stimulating the hydration of dicalcium silicate. Sodium sulfate dissolves, raising the pH of the system, disrupting the glassy silica-oxygen network of the slag, and releasing active silica. Sulfate ions and gypsum form a complex sulfate-activated system, promoting the formation of more hydrated calcium sulfoferrate (aluminate) and shortening the setting time. Triisopropanolamine complexes calcium ions to form soluble complexes, while sodium sulfate provides highly mobile sodium ions, together constructing a "high-speed ion channel" that allows calcium and sulfate ions to rapidly diffuse to the reaction interface.

[0015] In the early stages, sodium sulfate accelerates the dissolution of aluminate, leading to rapid nucleation of hydrated calcium sulfoferrate (aluminate). In the later stages, triisopropanolamine continuously excites the silicate phase, and the CSH gel incrementally fills the gaps in the hydrated calcium sulfoferrate (aluminate) framework, forming a "rigid-tough" dual-network structure.

[0016] Sodium sulfate promotes the staggered formation of hydrated calcium sulfoferrate (aluminate) crystallization and triisopropanolamine-induced CSH gel on a timescale, avoiding localized expansion stress concentration and reducing microcracks. Sodium sulfate reduces the surface tension of the pore solution, and combined with the water-retaining effect of triisopropanolamine, reduces drying shrinkage.

[0017] For chloride ions, there is interlayer adsorption of hydrated calcium sulfoferrate (aluminate), combined with physical barrier properties of CSH gel. For sulfate ions, the formation of ettringite is avoided by converting them into a stable hydrated calcium sulfoferrate (aluminate) phase. This dual mechanism enhances corrosion resistance.

[0018] Preferably, the mass ratio of triisopropanolamine to sodium sulfate in the accelerator mixture is 1:0.8-1.4.

[0019] By adopting the above technical solution, sodium sulfate is the main provider of alkalinity in the system. When the sodium sulfate content is too low, the release of active silica decreases, leading to a delay in the early hydration reaction; the formation of hydrated calcium sulfoferrate (aluminate) decreases, making it difficult to form an early strength framework; the accumulation of unreacted aluminate / ferrate phases increases the risk of later expansion; it also leads to an imbalance in ion migration channels. When the sodium sulfate content is too high, excess sulfate ions react with the residual aluminum phase in the later stage to form delayed ettringite, inducing microcracks; unconsumed sulfate ions combine with calcium ions to precipitate gypsum dihydrate, blocking capillary channels and hindering CSH gel deposition; excess sodium ions will reduce the corrosion resistance coefficient. Therefore, after extensive research and experimental verification, the applicant finally determined that the mass ratio of triisopropanolamine to sodium sulfate in the accelerator mixture of this application should be as described above.

[0020] Preferably, the additive is a mixture of two additives: activated alumina and an accelerator.

[0021] By employing the above technical solution, activated alumina serves as a silicon-aluminum source carrier, providing aluminum ions required for the geological polymerization reaction and forming a three-dimensional network framework. The accelerators are divided into ionic accelerators and organic amine accelerators. Ionic accelerators can synergistically generate hydrated calcium sulfoferrate (aluminate) with alumina, enhancing early strength; organic amines can complex calcium ions, directionally migrating them to the slag surface. Furthermore, the mesoporous structure of alumina forms "high-speed ion channels," through which accelerator ions rapidly diffuse.

[0022] Preferably, in the dual-additive mixture, the activated alumina is fly ash and the accelerator is triethanolamine.

[0023] By employing the above technical solution, the hydroxyl and nitrogen atoms in the triethanolamine molecule provide lone pairs of electrons, forming stable complexes with aluminum and calcium ions in fly ash. This process disrupts the silica-alumina glass network on the surface of fly ash particles, increasing the dissolution rate of the previously encapsulated active aluminum and silicon, and improving the effective utilization rate of the fly ash's specific surface area. Triethanolamine promotes the rapid dissolution of aluminum ions in fly ash and combines with calcium and sulfate ions in the system, accelerating the formation of ettringite, thereby significantly improving early strength. Simultaneously, triethanolamine inhibits aluminum hydroxide precipitation, ensuring the continuous participation of active aluminum in CASH gel formation, increasing the proportion of hexacoordinate aluminum in the gel, and enhancing microstructure density.

[0024] Triethanolamine promotes the full hydration of fly ash, increasing the amount of CASH gel and enhancing its layered structure's physical adsorption capacity for chloride ions. The active alumina in the fly ash synergistically generates more aluminum-containing phases with the calcium ions released by triethanolamine, chemically binding chloride ions and improving the corrosion resistance coefficient. The triethanolamine-induced CASH gel forms a dense network, simultaneously promoting the uniform deposition of amorphous calcium carbonate in the pores, resulting in a dual enhancement of "physical filling + chemical cementation." The improved interfacial bonding between fly ash particles and the gel significantly reduces microcracks.

[0025] Preferably, the mass ratio of fly ash to triethanolamine in the dual-additive mixture is 250:1-10.

[0026] By adopting the above technical solution, when the triethanolamine content is too low, triethanolamine is unable to fully destroy the glassy structure of fly ash, resulting in slow early hydration reaction; moreover, the amount of gel formation is insufficient, and the erosion resistance coefficient decreases. Therefore, after extensive research and experimental verification, the applicant finally determined that the mass ratio of fly ash to triethanolamine in the dual-additive mixture of this application should be as described above.

[0027] Preferably, the additive is a mixture of three additives: activated calcium carbonate, activated alumina, and an accelerator.

[0028] By employing the above technical solution, activated calcium carbonate provides calcium ions and nano-nucleation sites, synergistically forming ettringite with gypsum. Activated alumina provides aluminum ions to promote the formation of ettringite and CASH gel, where calcium carbonate supplements calcium, and the promoter depolymerizes the glass to release aluminum. The promoter disrupts the glass and regulates the hydration pathway, optimizing the aluminum phase release rate and avoiding local pH fluctuations.

[0029] Preferably, the weight parts of each component in the three additive mixture are 0.01-5 parts of active calcium carbonate, 0.01-5 parts of active alumina, and 0.01-1 parts of accelerator.

[0030] Secondly, this application provides a method for preparing a high corrosion-resistant cementitious material composition for all solid waste, using the following technical solution: A method for preparing a high corrosion-resistant cementitious material composition made entirely from solid waste, comprising the following steps: The metal tailings, granulated blast furnace slag powder, gypsum, calcareous raw materials, and additives in the formula are first ground separately, and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0031] In summary, this application has the following beneficial effects: This application utilizes a specific blend of metal tailings, slag powder, gypsum, and calcareous raw materials of varying types and fineness, formulated in a specific ratio. Under conditions requiring no high-temperature calcination, the hydration activity of the metal tailings and granulated blast furnace slag powder is activated through the combination of solid waste mineral phases and additives. Activated calcium carbonate and activated alumina can induce the in-situ growth of two-dimensional hydration products of single-carbon hydrated calcium aluminate, effectively fixing harmful ions in the coastal environment and thus improving the corrosion resistance of this cementitious material. The addition of accelerators further optimizes the hydration environment, regulating the types, forms, and distribution of hydration products, thereby improving the density and long-term durability of the cementitious material's microstructure. Detailed Implementation

[0032] The raw materials in this application include the following: Metal tailings: including but not limited to one or more types of iron tailings, copper tailings, lead-zinc tailings, and gold tailings; before being ground together with other components, they must be pre-dried and pre-ground separately. The moisture content after drying should be controlled below 0.5%, and the Blaine surface area after separate grinding should not be less than 500 m². 2 / kg.

[0033] Granulated blast furnace slag powder: Granulated blast furnace slag powder of grade S95 or higher conforming to the standard of "Granulated Blast Furnace Slag Powder for Cement, Mortar and Concrete" (GB / T18046-2017), with a Blaine specific surface area of ​​not less than 450 m². 2 / kg.

[0034] Gypsum: Industrial by-product gypsum, including but not limited to one or more of desulfurized gypsum, fluorogypsum, phosphogypsum, and titanium gypsum, whose properties must meet the relevant requirements of "Industrial by-product gypsum for use in cement" (GB / T 21371-2019).

[0035] Calcium raw materials: used to provide an alkaline environment and calcium source, selected from one or more of the following: carbide slag, recycled micro powder, quicklime, hydrated lime, and chlor-alkali mud. The carbide slag is the carbide slag specified in T / NMSNXH 001, "Carbide Slag for the Production of Silicate Cement Clinker"; the recycled micro powder is particles with a particle size less than 75μm as specified in GB / T 25176-2010, "Recycled Fine Aggregate for Concrete and Mortar"; the recycled micro powder can refer to particles with a particle size less than 75μm as specified in GB / T 25176-2010, "Recycled Fine Aggregate for Concrete and Mortar"; the quicklime and hydrated lime can refer to the relevant standards of "Construction Quicklime" (JC / T 479-2013) and "Construction Hydrated Lime" (JC / T 481-2013), respectively.

[0036] Activated calcium carbonate includes, but is not limited to, one or more of the following: carbonized steel slag, carbonized recycled micro powder, carbonized red mud, carbonized fly ash, silicon carbide calcium slag, and nano-calcium carbonate, with a Blaine specific surface area of ​​not less than 450 m² before being ground in conjunction with other components. 2 / kg.

[0037] Activated alumina: including but not limited to one or more of fly ash, metakaolin, alumina slag, and nano-alumina, with a Blaine specific surface area of ​​not less than 450 m² before grinding with other components. 2 / kg.

[0038] Accelerators include, but are not limited to, one or more of the following: triisopropanolamine, triethanolamine, sodium sulfate, sodium bicarbonate, polyaluminum chloride, sulfoaluminate cement clinker, sodium aluminate, and aluminum hydroxide.

[0039] The present application will be further described in detail below with reference to embodiments and comparative examples.

[0040] Example 1 A method for preparing a high corrosion-resistant cementitious material composition from solid waste includes the following steps: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 0.5g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0041] Example 2-3 Based on the preparation method of Example 1, Examples 2-3 adjust the content of each component in the high corrosion-resistant cementitious material composition of all solid waste. The specific adjustments are shown in Table 1.

[0042] Comparative Examples 1-3 Comparative Example 1, based on the preparation method of Example 1, adjusted the preparation method as follows: 200g of iron tailings powder, 600g of granulated blast furnace slag powder, 150g of desulfurized gypsum, and 50g of silicate cement clinker are ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0043] Comparative Example 2, based on the preparation method of Example 1, adjusted the preparation method as follows: 400g of iron tailings powder, 400g of granulated blast furnace slag powder, 150g of desulfurized gypsum, and 50g of silicate cement clinker are ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0044] Comparative Example 3 was prepared using the same method as in Example 1, but without the addition of 0.5g of triisopropanolamine.

[0045] Performance testing The high corrosion-resistant cementitious material compositions of all solid waste from Examples 1-3 and Comparative Examples 1-3 were subjected to the following performance tests, and the test results are shown in Table 1.

[0046] 1. Compressive strength The compressive strength of the high corrosion-resistant cementitious material composition for solid waste was determined at 3 days, 7 days and 28 days according to GB / T 17671-2021.

[0047] 2. Corrosion resistance coefficient The 28-day erosion resistance coefficient of the high corrosion-resistant cementitious material composition for all solid waste was determined according to GB / T 38140-2019.

[0048] Table 1. Content (in g) of each component and performance test results of the all-solid waste high corrosion-resistant cementitious material compositions in Examples 1-3 and Comparative Examples 1-3.

[0049] Referring to Table 1, comparing Examples 1-3 and Comparative Examples 1-3, it can be seen that the all-solid waste high-corrosion-resistant cementitious material composition prepared using the above formula has better effects. The reason is that by compounding metal tailings, slag powder, gypsum, and calcareous raw materials in a certain proportion, and without the need for high-temperature calcination, the hydration activity of the metal tailings and granulated blast furnace slag powder is activated through the compatibility of solid waste mineral phases and additives. Activated calcium carbonate and activated alumina can induce the in-situ growth of two-dimensional hydration products of single-carbon hydrated calcium aluminate, effectively fixing harmful ions in the coastal environment and thus improving the corrosion resistance of this cementitious material. The addition of accelerators can effectively promote the generation of hydration products, allowing more hydration products to fill the pores, increasing the density and structural stability of the cementitious material, thereby further improving the corrosion resistance and long-term durability of the cementitious material. In addition, by supplementing activated calcium carbonate, activated alumina, and chemical accelerators, the hydration products are generated more quickly in the early stages, effectively solving the problem of low early strength caused by the large-scale incorporation of low-activity tailings.

[0050] The formula achieves a high utilization rate of up to 40% for metal tailings, with an overall solid waste content of 100%, providing a large-scale disposal method for bulk metal tailings and industrial by-products such as gypsum and steel slag, which is of great environmental significance. The preparation process of the cementitious material does not involve high-temperature calcination, but only drying, grinding and mixing, which has significant safety, environmental protection and low-carbon advantages compared with traditional cement.

[0051] Examples 4-8 Example 4 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 0.5g of triethanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0052] Example 5 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 0.5g of sodium sulfate were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0053] Example 6 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 0.5g of an accelerator mixture were first ground separately, then mixed evenly to obtain a high corrosion-resistant cementitious material composition from all solid waste. The accelerator mixture was composed of triisopropanolamine and sodium sulfate, with a mass ratio of triisopropanolamine to sodium sulfate of 1:1.1.

[0054] Example 7 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 0.5g of an accelerator mixture were first ground separately, then mixed evenly to obtain a high corrosion-resistant cementitious material composition from all solid waste. The accelerator mixture was composed of triisopropanolamine and triethanolamine in a mass ratio of 1:1.1.

[0055] Example 8 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 0.5g of accelerator mixture were first ground separately, then mixed evenly to obtain a high corrosion-resistant cementitious material composition from all solid waste. The accelerator mixture was composed of triethanolamine and sodium sulfate in a mass ratio of 1:1.

[0056] The high corrosion-resistant cementitious material compositions of solid waste from Examples 4-8 were subjected to the above performance tests, and the test results are shown in Table 2.

[0057] Table 2 Performance test results for Examples 1 and 4-8

[0058] Referring to Table 2, a comparison of Examples 1 and 4-8 shows that triisopropanolamine, when used as the accelerator, produces a more effective high-corrosion-resistant cementitious material composition for solid waste compared to triethanolamine and sodium sulfate. This is because triisopropanolamine reduces the surface energy of slag particles, promotes uniform dispersion of mineral powder, increases the contact area for hydration reactions, and accelerates early CSH gel nucleation. At the same dosage, triisopropanolamine is more effective than triethanolamine in improving the fluidity of the cementing system, reducing water demand, and indirectly increasing density. Triisopropanolamine accelerates the depolymerization of slag glass and promotes the hydration of aluminoferrites, while triethanolamine mainly activates aluminates. By complexing iron / aluminum ions, triisopropanolamine accelerates their reaction with gypsum to generate hydrated calcium sulfoferrite (aluminate), shortening the setting time while increasing 3-day strength. In the later stages, triisopropanolamine continuously promotes the hydration of inert phases such as dicalcium silicate in the slag, generating more CSH gel and improving 28-day compressive strength. Triisopropanolamine promotes the formation of large quantities of hydrated calcium sulfoferrate (aluminate) and CSH gel, filling capillary pores and reducing total porosity. The dense structure blocks chloride / sulfate ion penetration, increasing the corrosion resistance coefficient.

[0059] When both triisopropanolamine and sodium sulfate are used as accelerators, the effect of the prepared high corrosion-resistant cementitious material composition for solid waste is further improved. This is because triisopropanolamine complexes calcium ions to form soluble complexes, while sodium sulfate provides highly mobile sodium ions, together constructing a "high-speed ion channel" that allows calcium and sulfate ions to diffuse rapidly to the reaction interface. In the early stages, the composition accelerates the dissolution of aluminate through sodium sulfate, leading to rapid nucleation of hydrated calcium sulfoferrate (aluminate). Later, triisopropanolamine continuously excites the silicate phase, and the increased CSH gel fills the gaps in the hydrated calcium sulfoferrate (aluminate) framework, forming a "rigid-tough" dual-network structure. The sodium sulfate-promoted crystallization of hydrated calcium sulfoferrate (aluminate) and the triisopropanolamine-induced CSH gel are generated at staggered time scales, avoiding localized expansion stress concentration and reducing microcracks. Sodium sulfate reduces the surface tension of the pore solution, and combined with the water-retaining effect of triisopropanolamine, reduces drying shrinkage. For chloride ions, hydrated calcium sulfoferrate (aluminate) is adsorbed between layers, and the CSH gel provides physical barrier protection. For sulfate ions, the formation of ettringite is avoided by converting them into a stable hydrated calcium sulfoferrate (aluminate) phase. This dual mechanism enhances corrosion resistance.

[0060] Examples 9-10 Examples 9-10 are based on the preparation method of Example 6, but the mass ratio of triisopropanolamine and sodium sulfate is adjusted. The specific adjustments are shown in Table 3.

[0061] The high corrosion-resistant cementitious material compositions of solid waste from Examples 9-10 were subjected to the above performance tests, and the test results are shown in Table 3.

[0062] Table 3. Mass ratio of triisopropanolamine and sodium sulfate and performance test results in Examples 1, 6, and 9-10.

[0063] Referring to Table 3, a comparison of Examples 1, 6, and 9-10 shows that as the mass percentage of sodium sulfate increases, the effectiveness of the high corrosion-resistant cementitious material composition for solid waste exhibits a trend of first increasing and then decreasing. This is because: sodium sulfate is the main provider of alkalinity in the system. When the sodium sulfate content is too low, the release of active silica decreases, leading to a delay in early hydration reactions; the formation of hydrated calcium sulfoferrate (aluminate) decreases, making it difficult to form an early strength framework; the accumulation of unreacted aluminate / ferrate phases increases the risk of later expansion; and it also leads to an imbalance in ion migration channels. When the sodium sulfate content is too high, excess sulfate ions react with the residual aluminum phase in the later stages to form delayed ettringite, inducing microcracks; unconsumed sulfate ions combine with calcium ions to precipitate gypsum dihydrate, blocking capillary channels and hindering CSH gel deposition; and excess sodium ions reduce the corrosion resistance coefficient.

[0064] Examples 11-13 Example 11 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 10g of nano-calcium carbonate were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0065] Example 12 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 10g of nano-alumina were first ground separately, and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0066] Example 13 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, and 10g of fly ash were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0067] The high corrosion-resistant cementitious material compositions of all solid waste in Examples 11-13 were subjected to the above performance tests, and the test results are shown in Table 4.

[0068] Table 4 Performance test results for Examples 1 and 11-13

[0069] Referring to Table 4, a comparison of Examples 1 and 11-13 shows that when only one type of additive is selected, the prepared high-corrosion-resistant cementitious material composition from all solid waste exhibits better results when using an accelerator. When nano-alumina is used as the activated alumina, the prepared high-corrosion-resistant cementitious material composition from all solid waste shows even better results compared to fly ash.

[0070] Examples 14-19 Example 14 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of nano-calcium carbonate, and 10g of nano-alumina are ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0071] Example 15 is based on the preparation method of Example 1, but with adjustments made to the preparation method: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of nano-calcium carbonate, and 1g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0072] Example 16 adjusts the preparation method based on the preparation method of Example 1: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of nano-alumina, and 1g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0073] Example 17 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of fly ash, and 1g of triethanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0074] Example 18 adjusts the preparation method based on the preparation method of Example 1: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of fly ash, and 1g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0075] Example 19 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of fly ash, and 1g of sodium sulfate were first ground separately, and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0076] The high corrosion-resistant cementitious material compositions of all solid waste in Examples 14-19 were subjected to the above performance tests, and the test results are shown in Table 5.

[0077] Table 5 Performance test results for Examples 1 and 14-19

[0078] Referring to Table 5, a comparison of Examples 1 and 14-19 shows that using two types of additives, especially the combination of activated alumina and accelerator, results in a better-performing all-solid-waste high-corrosion-resistant cementitious material composition. This is because activated alumina, as a silicon-aluminum source carrier, provides the aluminum ions required for the geological polymerization reaction and forms a three-dimensional network framework. Accelerators are divided into ionic accelerators and organic amine accelerators. Ionic accelerators can synergistically generate hydrated calcium sulfoferrate (aluminate) with alumina, enhancing early strength; organic amines can complex calcium ions, directing their migration to the slag surface. Furthermore, the mesoporous structure of alumina forms "high-speed ion channels," through which accelerator ions diffuse rapidly.

[0079] When the activated alumina is fly ash and the accelerator is triethanolamine, the prepared high-corrosion-resistant cementitious material composition for solid waste exhibits further improved performance. This is because the hydroxyl and nitrogen atoms in the triethanolamine molecule provide lone pairs of electrons, forming stable complexes with aluminum and calcium ions in the fly ash. This process disrupts the silica-alumina glass network on the surface of the fly ash particles, increasing the dissolution rate of the previously encapsulated active aluminum and silicon, and improving the effective utilization rate of the fly ash's specific surface area. Triethanolamine promotes the rapid dissolution of aluminum ions in the fly ash and combines with calcium and sulfate ions in the system, accelerating the formation of ettringite, thereby significantly improving early strength. Simultaneously, triethanolamine inhibits aluminum hydroxide precipitation, ensuring the continuous participation of active aluminum in the formation of CASH gel, increasing the proportion of hexacoordinate aluminum in the gel, and enhancing microstructure density.

[0080] Triethanolamine promotes the full hydration of fly ash, increasing the amount of CASH gel and enhancing its layered structure's physical adsorption capacity for chloride ions. The active alumina in the fly ash synergistically generates more aluminum-containing phases with the calcium ions released by triethanolamine, chemically binding chloride ions and improving the corrosion resistance coefficient. The triethanolamine-induced CASH gel forms a dense network, simultaneously promoting the uniform deposition of amorphous calcium carbonate in the pores, resulting in a dual enhancement of "physical filling + chemical cementation." The improved interfacial bonding between fly ash particles and the gel significantly reduces microcracks.

[0081] Examples 20-22 Example 20 adjusts the preparation method based on the preparation method of Example 1: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of fly ash, and 0.1g of triethanolamine were first ground separately, and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0082] Example 21 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of fly ash, and 0.5g of triethanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0083] Example 22 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 10g of fly ash, and 2g of triethanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0084] The high corrosion-resistant cementitious material compositions of solid waste from Examples 20-22 were subjected to the above performance tests, and the test results are shown in Table 6.

[0085] Table 6 Performance Test Tables for Examples 1, 17 and 20-22

[0086] Referring to Table 6, a comparison of Examples 1 and 20-22 shows that as the amount of triethanolamine added increases, the effect of the prepared high corrosion-resistant cementitious material composition for solid waste continuously improves until it stabilizes.

[0087] Examples 23-25 Example 23 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 25g of nano-calcium carbonate, 25g of nano-alumina, and 0.1g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0088] Example 24 is based on the preparation method of Example 1, but with adjustments: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 25g of nano-calcium carbonate, 25g of nano-alumina, and 0.5g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0089] Example 25 adjusts the preparation method based on the preparation method of Example 1: 400g of iron tailings powder, 435g of granulated blast furnace slag powder, 150g of fluorogypsum, 15g of carbide slag, 25g of nano-calcium carbonate, 25g of nano-alumina, and 1g of triisopropanolamine were ground separately and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

[0090] The high corrosion-resistant cementitious material compositions of all solid waste from Examples 23-25 ​​were subjected to the above performance tests, and the test results are shown in Table 7.

[0091] Table 7 Performance Test Tables for Examples 1 and 23-25

[0092] Referring to Table 7, a comparison of Examples 1 and 23-25 ​​shows that using three types of additives resulted in a better-performing all-solid-waste high-corrosion-resistant cementitious material composition. This is because: activated calcium carbonate provides calcium ions and nano-nucleation sites, synergistically forming ettringite with gypsum; activated alumina provides aluminum ions to promote the formation of ettringite and CASH gel, with calcium carbonate supplementing calcium and the promoter depolymerizing the glass to release aluminum. The promoter disrupts the glass and regulates the hydration pathway, optimizing the aluminum phase release rate and avoiding localized pH fluctuations.

[0093] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high corrosion-resistant cementitious material composition for all solid waste, characterized in that, The components include the following parts by weight: Metal tailings 0-40 parts, granulated blast furnace slag powder 40-85 parts, gypsum 5-20 parts, calcareous raw materials 0.5-3 parts, additives 0.01-6 parts; The additive includes at least one of activated calcium carbonate, activated alumina, and accelerator; The activated calcium carbonate includes at least one of the following: carbonized steel slag, carbonized recycled micro powder, carbonized red mud, carbonized fly ash, silicon carbide calcium slag, and nano-calcium carbonate. The activated alumina includes at least one of fly ash, metakaolin, alumina slag, and nano-alumina; The accelerator includes at least one of triisopropanolamine, triethanolamine, sodium sulfate, sodium bicarbonate, polyaluminum chloride, sulfoaluminate cement clinker, sodium aluminate, and aluminum hydroxide.

2. The all-solid waste high corrosion-resistant cementitious material composition according to claim 1, characterized in that: The additive is an accelerator, and the accelerator is triisopropanolamine.

3. The all-solid waste high corrosion-resistant cementitious material composition according to claim 1, characterized in that: The additive is an accelerator, which is a mixture of triisopropanolamine and sodium sulfate.

4. The all-solid waste high corrosion-resistant cementitious material composition according to claim 3, characterized in that: The mass ratio of triisopropanolamine to sodium sulfate in the accelerator mixture is 1:0.8-1.

4.

5. The all-solid waste high corrosion-resistant cementitious material composition according to claim 1, characterized in that: The additive is a mixture of two additives: activated alumina and an accelerator.

6. The all-solid waste high corrosion-resistant cementitious material composition according to claim 5, characterized in that: In the dual-additive mixture, the activated alumina is fly ash and the accelerator is triethanolamine.

7. The all-solid waste high corrosion-resistant cementitious material composition according to claim 6, characterized in that: The mass ratio of fly ash to triethanolamine in the dual-additive mixture is 250:1-10.

8. The all-solid waste high corrosion-resistant cementitious material composition according to claim 1, characterized in that: The additive is a mixture of three additives: activated calcium carbonate, activated alumina, and an accelerator.

9. The all-solid waste high corrosion-resistant cementitious material composition according to claim 8, characterized in that: The weight parts of each component in the three-additive mixture are 0.01-5 parts of active calcium carbonate, 0.01-5 parts of active alumina, and 0.01-1 parts of accelerator.

10. A method for preparing the all-solid waste high corrosion-resistant cementitious material composition according to any one of claims 1-9, characterized in that, Includes the following steps: The metal tailings, granulated blast furnace slag powder, gypsum, calcareous raw materials, and additives in the formula are first ground separately, and then mixed evenly to obtain a high corrosion-resistant cementitious material composition of all solid waste.

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